1. Field of the Invention
The present invention relates to a single crystal silicon carbide thin film fabrication method and a fabrication apparatus of the same.
2. Prior Art
Since a single crystal silicon carbide (SiC) is not only excellent in thermal and chemical stability but also tough in mechanical strength and durable to radiation of radiation beams, it has been drawing attention as a substrate for epitaxial growth of gallium nitride widely used for a semiconductor device material of the next generation as well as a substrate of light emitting device.
For such a single crystal silicon carbide thin film fabrication method, a sublimation recrystallization method using a silicon carbide seed crystal, a plasma CVD method and the like have become a main stream.
However, a conventional sublimation recrystallization method requires a ultra high temperature process in the vicinity of 1,700xc2x0 C. in addition to the necessity of a silicon carbide seed crystal with a high purity. Whereas, in the plasma CVD method, a film-formation chamber is required to be kept highly vacuum in the film-formation process. That is, both methods are rather problematic in terms of the cost and the time. Further, these conventional methods, it is difficult to satisfy the requirement of fabrication with a large diameter.
The present invention has been achieved taking account of the above described situations and aims to provide a single crystal silicon carbide thin film fabrication method capable of economically and easily fabricating a single crystal silicon carbide thin film and a fabrication apparatus for the method.
A single crystal silicon carbide thin film fabrication method according to the invention is to convert a silicon layer on the surface of a SOI substrate for film-formation into a single crystal silicon carbide thin film by a chemical reaction carried out by setting the SOI substrate for film-formation in a film-formation chamber and increasing the ambient temperature of the film-formation chamber to 1,200 to 1,405xc2x0 C. while passing hydrogen gas and passing also a hydrocarbon-based gas being kept in a ratio of 1 to 5% by volume to hydrogen gas.
Further, a single crystal silicon carbide thin film fabrication apparatus according to the invention comprises a film-formation chamber adapted to receive a SOI substrate for film-formation, a gas supply means for supplying various gases necessary to fabricate a single crystal silicon carbide thin film to the film-formation chamber, a gas treatment means for treating gases supplied to the film-formation chamber, and a temperature control means for controlling the temperature of the film-formation chamber.